<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<input type="text" id="user" value="admin">
<div style="height: 50px">
    <div id="model">
        <span>显示</span>
        <div>12345</div>
    </div>
</div>
<script>
    function demo() {
        var obj=document.getElementById('model');
        alert(obj.value);
        alert(obj.innerHTML);
        alert(obj.innerText);
    }
    demo();
</script>
</body>
</html>